Weird Science looks for vacancies at the hermit crab hotel

Social exchanges among hermits, the beauty pageantry of corporate leadership, …

They may still be crabs, but they're not hermits: This is a fascinating bit of social behavior that I had no idea existed. For hermit crabs, decent shells are a scarce commodity, and they've evolved a social means of optimizing shell occupancy that researchers have termed a vacancy chain. This new observational study describes two types of vacancy chains, synchronous and asynchronous. The asynchronous forms might be just what you expect, as one crab will swap to a new shell and abandon its old one, but that will later be found by another, which abandons its own, and so on.

But in the synchronous case, crabs will actually line up in size order when presented with a suitable unoccupied shell, so that any swapping can quickly shuffle shells down the vacancy chain. "They spend hours queuing up, and then the chain fires off in seconds, just like a line of dominoes," said one of the authors. There are also behaviors associated with getting the chain together. Crabs that find an overly large shell will actually camp out next to it, hoping that intermediate-sized peers will come along. Others, when in need of a new shell, will piggy-back on a large crab, hoping to be carried to a new home.

This probably explains a lot: The leadership of large companies, and the compensation that goes with it, is a matter of looks. A team of researchers at Duke had nearly 2,000 test subjects look at paired pictures, and found that photos belonging to CEOs were rated as more likable and competent than average. The larger the firm, the more pronounced the effect, and compensation apparently correlated with the visual appearance, as well. The authors find this worrisome, given that there's no evidence tying actual competence to the appearance thereof. "We find no evidence that the firms of competent looking CEOs perform better," they write. "Essentially, the 'look' of competence says very little about effective competence."

Stick around here, or your brain will shrink: This one's a bit counterintuitive, at least from my perspective. You might think that animals that perform seasonal migrations between continents would require a bit of extra mental horsepower to handle the task. Instead, a study of passerine birds (aka, perching birds or songbirds) indicates that migration causes a selective pressure for smaller brain sizes. According to the authors' analysis, over two-thirds of the inverse correlation between migratory distance and brain size can be ascribed to a direct impact of migration. They suggest that the metabolic demands of long-distance travel may have a stronger influence than cognitive needs.

This, from an author in the land of CCTV: An author from the UK, inspired by a "making of" documentary on a nature documentary, considers the whole filming process a violation of the animals' right to privacy, and accuses those who have no problem with it of "speciesism." These "making of" videos, however, make it clear that the whole challenge is often to ensure that the animal never recognizes that a human is there. With no knowledge of a human's presence, no concept of filming, and no concept of privacy, I'm at a loss to figure out how a violation can take place from an animal's perspective.

Things get a bit weirder still in the press release, where these musings are termed "research," and that the aim of it is to "encourage debate." I suspect most of the debate will involve questions of what, precisely, has been smoked.

Reward-driven individuals just can't help themselves: We all know the type: for some people, everything—friendly basketball games, a round of a board game—becomes a winner-take-all contest. Now, researchers have evidence that suggests these hypercompetitive individuals view all wins as equally rewarding. The researchers began with the supposition that the most reward-focused individuals would bring their best effort to the fore when presented with a trial that promised a payoff. Instead, everybody managed to bring their A-game for those. What the testing showed is that the competitive can't seem to shut this tendency down, and got keyed-up for everything—whether there was a reward on the line or not. As a result, they showed the largest performance gains relative to their peers when there was no reward for success.

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